From ccb5b8fee774cb5f419adbdd30c5a9bdfd2470e4 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sun, 31 Mar 2019 13:04:12 -0700 Subject: crypto: crct10dif-generic - fix use via crypto_shash_digest() commit 307508d1072979f4435416f87936f87eaeb82054 upstream. The ->digest() method of crct10dif-generic reads the current CRC value from the shash_desc context. But this value is uninitialized, causing crypto_shash_digest() to compute the wrong result. Fix it. Probably this wasn't noticed before because lib/crc-t10dif.c only uses crypto_shash_update(), not crypto_shash_digest(). Likewise, crypto_shash_digest() is not yet tested by the crypto self-tests because those only test the ahash API which only uses shash init/update/final. This bug was detected by my patches that improve testmgr to fuzz algorithms against their generic implementation. Fixes: 2d31e518a428 ("crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework") Cc: # v3.11+ Cc: Tim Chen Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/crct10dif_generic.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) (limited to 'crypto') diff --git a/crypto/crct10dif_generic.c b/crypto/crct10dif_generic.c index 8e94e29dc6fc..d08048ae5552 100644 --- a/crypto/crct10dif_generic.c +++ b/crypto/crct10dif_generic.c @@ -65,10 +65,9 @@ static int chksum_final(struct shash_desc *desc, u8 *out) return 0; } -static int __chksum_finup(__u16 *crcp, const u8 *data, unsigned int len, - u8 *out) +static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out) { - *(__u16 *)out = crc_t10dif_generic(*crcp, data, len); + *(__u16 *)out = crc_t10dif_generic(crc, data, len); return 0; } @@ -77,15 +76,13 @@ static int chksum_finup(struct shash_desc *desc, const u8 *data, { struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - return __chksum_finup(&ctx->crc, data, len, out); + return __chksum_finup(ctx->crc, data, len, out); } static int chksum_digest(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out) { - struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); - - return __chksum_finup(&ctx->crc, data, length, out); + return __chksum_finup(0, data, length, out); } static struct shash_alg alg = { -- cgit v1.2.3